I believe you are mistaken in your chronology. The all wood plane was definitely first, but the all metal plane was second. The "transitional" plane came last in an effort to recruit the many buyers who loved the smooth feel of wood on wood, as opposed to the drag of metal on wood. This "new" design allowed those buyers to transition to the mechanical adjustments without sacrificing the smooth, almost effortless feel of their beloved wood on wood.
@handcraftedbygrbroussard361 yea one side is glass that is where the grit size is written. The other side is the actually abrasive. I have that exact stone
